Automatic protective device.



K. KARPPINEN.

AUTOMATIC PROTECTIVE DEVICE.

APPLICATION FILED JUNE 7, 1917- Patented May 28,1918.

Earl Earppinerv, I 70 fi flbnz ys UNITED STATES PATENT OFFICE.

KARL KARPPINEN, OF BRISBANE, QUEENSLAND, AUSTRALIA, ASSIGNOR OF ONE-HALF TO THOMAS GARRETT AND PAUL JENNER URE, BOTH OF BRISBANE, AUSTRALIA.

AUTOMATIC PROTECTIVE DEVICE.

Specification of Letters Patent.

Patented May 28, 1918.

To all whom it may concern.-

Be it known that I, KARL KARPPINEN, a subject of the King of the United Kingdom of Great Britain and Ireland, residing at Coarparoo, Brisbane, in the State of Queensland, Australia, have invented new and useful Improvements in Automatic Protective Devices, of which the following is a specification.

This invention relates to a method and an automatic device for shunting excessive electric potentials and amperages and also for automatically reestablishing original line for transit of current as soon as normal conditions again exist.

The object of the invention, is, firstly, to protect electrical instruments and lines from electrical overcharge and lightning discharges; secondly, to minimize the risk of fires from overheating of live wires through overcharging; thirdly, to provide a relay connecting system operated by different electrical potentials and amperages; fourthly, to save time and labor, the device obviating the necessity of repair or replacement after excessive electrical potentials and amperages have been shunted to earth; fifthly, in use as a relay; sixthly, as shunt protector from overcharging accumulators.

This invention consists in applying the principle of expansion and contraction of a conducting medium when subjected respectively to electrical overload and relief of overload. by automatic shunt, in conjunction with a lever oscillating in a bracket on pivot points at one extremity; from about this extremity beneath the lever is a spring of adjustable tension which supports the lever causing contact at its other extremity, in two places, one with the electric current intake bracket, and the other which makes contact just prior to the former through an adjustable spring set on top of side of contact end of lever with a metallic connection running to earth or to any absorber of high potential and amperage.

In the same plane and above and approximately parallel to the lever is affixed a wire of known electrical carrying capacity one end to the electrical current intake bracket by a slotted nut and lock nut and the other end to the top of the lever directly above the pivot pins.

The tension of this wire between these two points is such, that it overcomes the tension of the spring thus causing the lever to make contact on a rest which is not in electrical connection with the metallic connection. running to earth; therefore, the only path for the electric current to fiow is through the electrical intake bracket along intake bracket B and a conducting bracket C for supporting a lever hereinafter referred to.

Adjacent and at right angles to the bracket B but not in contact therewith, is, mounted upon the base A a swan neck bracket D which makes a contact with the earth line.

In the jaws of the bracket C is pivoted a lever E, the tension of which pivoting function is governed by an adjusting screw and lock nut F by pressing the pivot pin upon which the lever E is mounted into the pivot hole in the opposite side of the bracket.

Fixed on the base A beneath the lever E at or adjacent to the bracket C is a spring G, the tension of which is adjusted by a screw H; this spring is of sufficient tension to raise the lever E so that the free end thereof makes contact, first in point of time at the point I (an adjustable contact point) on the bracket D by means of a fiat spring J attached to the top side of the lever, and secondly, contacts with a lug K projecting from the intake bracket B.

On the base A immediately below the free end of the lever E and insulated from electrical connection, is a rest plate L fitted with an adjusting contact screw M.

In the same plane and approximately parallel to the lever E and above it, is a c0nducting medium N of known capacity and resistance (preferably wire) stretched be tween the brackets B and C, the tension of which is adjusted by a screw 0 and lock nut P, pulling on the wire, the one end which is attached by a screw and washer T to the heel of the lever E above the pivot axle, and the other end to the intake bracket B by means oi a slotted nut R and lock nut S (shown on the drawings to enlarged. scale).

For the purpose of shunting excessive electrical potentials of an alternating nature e. g. lightning, et cetera, there is in metallic contact (or by extensionlaterally of the base of the swan-neck bracket D) an adjustable toothed air gap facing the base of the electrical current intake b acket id.

The extension of the base of the swan neck bracket D (or plate in metallic centact therewith) is indicated by the letter U; upon this plate is a toothed plate V with an adjustable screw W working as an eccentric in an oval (shown in dotted lines) in. the bottom plate, which adjusts the air gap and is finally locked by lock screw X.

In operation the current normally traverses to the instruments per medium of. the wire; as soon as the normal carrying capacity of the wire is exceeded by an excess ot po tential or amperage, the wire becomes hot and expands, thus releasing the tension in opposition to the spring tension, permitting the latter to operate and to lift the lever in order to make contact, firstly in point of time at the metallic connection running to earth or to any absorber as previously mentioned, and secondly at the current intake bracket.

As soon as the wire becomes cool by being relieved of the electrical overload, the contraction of the wire exerts a pull upon the.

lever counteracting the tension of the spring underneath the lever; this causes automatic re'e'stablishment of the original line which condition of things will endure until the normal electrical carrying capacity is again exceeded, when the excessive electrical potential and amperage will be shunted to earth.

What. I do claim, as my invention, and desire to secure by Letters Patent is z- 1. In an automatic device for shunting excessive electrical potentials and amperages and subsequently recstablishing original line the combination of an electric current intake bracket, a conducting bracket, a grounded bracket, a lever pivotally supported in said conducting bracket and having its free end arranged to contact with said intake bracket, a spring contact carried by said lever and arranged to be brought into enga ement with said rounded. bracket a.

m b t"; 7

conductor connected between said intake bracket and lever through which the current for the original line normally passes, said conductor adapted to hold the lever out of contact with said intake bracket and the spring contact out 01": engagement with the grounded bracket, but. also adapted to expand when heated consequent upon overload to release said lever and spring contact, a pressure spring bearing upon said lever and adapted to cause the lever to make contact with said intake bracket and the spring contact with said grounded bracket, and adjusting means to vary the pressure of said last-named spring, substantially as de scribed.

2. in an automatic device for shunting excessive electrical potentials and amperand subsequently reestablishing original line, the combination of an electric intake bracket, a conducting bracket, a grounded bracket, a lever having one end. pivotally supported in said. contact bracket and having its other end adapted to make contact with said intake bracket, a springcontact carried on said lever and, adapted to engage said grounded bracket, a metallic conductor connected at one end to the pivotal end of said. lever, a nut having a slot for receiving the other end of said conduc tor, a threaded bolt mounted. for adjustment in said intake bracket for adjustably hold.- ing said slotted nut, a lock nut on said bolt. for holding said slotted nut in adjusted position thereon, said conductor normally forming the original line and holding the lever out of contact with said intake bracket and said spring contact out. oi engagement with said grounded bracket but adapted to expand when heated consequent upon overload to release said. lever, and a pressure spring for moving said, lever into. contact with said intake bracket and said spring contact into engagement with said grounded bracket when said, conductor is overheated, substantially as described.

3. In an automatic device for shunting excessive electrical potentials and amperages and subsequently reestablishing original line, the combination of an intake bracket, a conducting bracket, a. grounded bracket, a plate in electrical connection with said grounded bracket having a toothed edge arranged near said intake bracket, means for adjusting said plate toward and from. said intakebracket, a lever pivoted in said conducting bracket and adapted to make contact with. said intake 11-5 bracket, :1 contact carried by said lever and adapted to engage said grounded bracket, current receiving means stretched between said intake bracket and lever "for normally holding the lever and contact carried there- 12 0 by out of engagement with said intake and grounded brackets but adapted to expand when heated by overload to release said lever, and means for moving said lever and contact when released into engagement with said intake and grounded brackets, respectively, substantially as described.

4. In an automatic device for shunting excessive electrical potentials and amperages and subsequently reestablishing ori,gi- 13 0 nal line, the combination of an intake bracket, a conducting bracket, a grounded bracket, a plate in electrical connection with said grounded bracket and having a toothed edge adjacent said intake bracket, an eccentric for shifting said plate to adjust the toothed edge with respect to said intake bracket, a lever pivoted in said conducting bracket and having its free end arranged to make contact with said intake bracket, a threaded bolt adjustably carried by said intake bracket, means to hold said bolt in adj usted position, a slotted nut adjustable along said bolt, a lock nut for holding said nut in the adjusted position, a metallic conductor having one end connected to the pivotal end of said lever and the other end secured in the slot in the slotted nut, said conductor forming a part of the original line and adapted to hold said lever out of contact with said intake bracket but to become heated and expand on overload, a spring contact carried by said lever and arranged to make contact with said grounded bracket but normally held disengaged by said conductor, a pressure spring for moving said lever and spring contact into engagement with said intake and grounded brackets when the con ductor expands, and a set screw for adjusting the pressure of said last-named spring, substantially as described.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

KARL KARPPINEN.

Witnesses:

J. S. BIoKnR'roN, G. H. LEGGE.

Copies of this patent may be obtained for five cents each, by addressing the "Commissioner of Patents, Washington, D. G. 

